The present invention relates to a disposable absorbent article used for absorption and containment of body wastes and to a method of making the same. The invention particularly relates to a disposable absorbent article such as an open or pull-on type diaper for an infant or incontinent patient or training pants and a method of making the same. Regarding the method, the invention particularly to a method comprising the step of attaching waist-surrounding elastic members to a base sheet functioning to support an absorbent panel and to hold this in close contact with a wearer's body.
WO 01/13843 A1 (hereinafter referred to as “Citation 1”) relating to an absorbent article such as a disposable diaper discloses a structure comprising a plurality of elastic members provided in a rear waist region of the article and fastener means detachably connecting the rear waist region with a front waist region of the article wherein the fastener means are fixed to the rear waist region so as to overlap the elastic members.
Japanese Patent No. 3096152 (hereinafter referred to as “Citation 2”) relating to a disposable diaper discloses a structure comprising front and rear waist regions previously connected to each other so that the diaper may be selectively used as an open or pull-on type diaper, elastic members attached to front and rear waist regions, respectively, a pair of fastener means attached to transversely opposite side edge portions of the front waist region, respectively, another fastener means attached to the rear waist region so as to cooperate with those on the front waist region and a pair of tear off lines provided along the transversely opposite side edge portions of the front waist region, respectively, so that, if desired, the front waist region can be torn off from the rear waist region.
In the case of the absorbent article disclosed in Citation 1, the fastener means are fixed to the rear waist region so as to overlap the elastic members, so the fastener means are formed with gathers as the elastic members contracts. Such gathers make it difficult to bring the fastener means in a firm engagement with a landing zone and an unstable engagement is accompanied with a problem that the fastener means may be unintentionally disengaged from the landing zone.
As one of measures to overcome such a problem, it may be contemplated that none of the elastic members is distributed over the part of the waist region to be provided with the fastener means. While it is technically possible to provide the waist region partially with the elastic members, such a measure is not suitable for a mechanical apparatus driven at a high speed to mass produce the article as described herein at a low cost. For this reason, in generally, the elastic members are provided along a full length of a waist-surrounding circumference and the fastener means are attached to the waist region so as to overlap these elastic members.
In the case of the diaper disclosed in Citation 2, the front waist region is provided along its transversely opposite side edge portions with a pair of tear off lines, respectively, along which the front waist region are torn off from the rear waist region. Assumed that these waist regions are formed by a nonwoven fabric made of staple fibers or continuous filaments of synthetic resin as this is usually the case and particularly such a nonwoven fabric contains fibers or filaments oriented to cross the tear off direction defined by the tear off lines, it is difficult to tear the front waist region off from the rear waist region.